Systems and Methods Using Cryptography to Protect Secure Computing Environments

• US 20080031461A1
• Filed: 08/20/2007
• Published: 02/07/2008
• Est. Priority Date: 08/12/1996
• Status: Abandoned Application

• Current Assignee: Intertrust Technologies Corporation (Fidelio Acquisition Co LLC)
• Original Assignee: Intertrust Technologies Corporation (Fidelio Acquisition Co LLC)
• Inventors: Van Wie, David, Sibert, W., Shear, Victor
• Application Number:
  US11/841,446
• Publication Number:
  US 20080031461A1
• Time in Patent Office: Days
• US Class Current: 380/282
• CPC Class Codes: G06F 12/1483 using an access-table, e.g. matrix or list
• CPC Class Codes: G06F 21/10 Protecting distributed programs or content, e.g. vending or licensing of copyrighted material protection in video systems or pay television H04N7/16 ; Digital rights management [DRM]
• CPC Class Codes: G06F 21/51 at application loading time, e.g. accepting, rejecting, starting or inhibiting executable software based on integrity or source reliability
• CPC Class Codes: G06F 2211/007 Encryption, En-/decode, En-/decipher, En-/decypher, Scramble, (De-)compress
• CPC Class Codes: G06Q 20/02 involving a neutral party, e.g. certification authority, notary or trusted third party [TTP]
• CPC Class Codes: G06Q 20/085 involving remote charge determination or related payment systems
• CPC Class Codes: G06Q 20/12 specially adapted for electronic shopping systems
• CPC Class Codes: G06Q 20/24 Credit schemes, i.e. "pay after"
• CPC Class Codes: G06Q 20/3674 involving authentication
• CPC Class Codes: G06Q 20/3823 combining multiple encryption tools for a transaction
• CPC Class Codes: G06Q 20/3825 Use of electronic signatures
• CPC Class Codes: G06Q 20/401 Transaction verification
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 20/00159 Parental control systems
• CPC Class Codes: G11B 20/00173 wherein the origin of the content is checked, e.g. determining whether the content has originally been retrieved from a legal disc copy or another trusted source
• CPC Class Codes: G11B 20/00188 involving measures which result in a restriction to authorised devices recording or reproducing contents to/from a record carrier
• CPC Class Codes: G11B 20/00195 using a device identifier associated with the player or recorder, e.g. serial numbers of playback apparatuses or MAC addresses
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00543 wherein external data is encrypted, e.g. for secure communication with an external device or for encrypting content on a separate record carrier
• CPC Class Codes: G11B 20/00557 wherein further management data is encrypted, e.g. sector headers, TOC or the lead-in or lead-out areas
• CPC Class Codes: G11B 20/00688 : said measures preventing that a usable copy of recorded data can be made on another medium
• CPC Class Codes: G11B 20/0071 : involving a purchase action
• CPC Class Codes: G11B 20/00768 : wherein copy control information is used, e.g. for indicating whether a content may be copied freely, no more, once, or never, by setting CGMS, SCMS, or CCI flags
• CPC Class Codes: G11B 2220/216 : Rewritable discs
• CPC Class Codes: G11B 2220/218 : Write-once discs
• CPC Class Codes: G11B 2220/2562 : DVDs [digital versatile discs]; Digital video discs; MMCDs; HDCDs
• CPC Class Codes: G11B 2220/2575 : DVD-RAMs
• CPC Class Codes: G11B 27/031 : Electronic editing of digitised analogue information signals, e.g. audio or video signals
• CPC Class Codes: G11B 27/329 : on a disc [VTOC]
• CPC Class Codes: H04L 12/40104 : Security; Encryption; Content protection cryptographic protocols H04L9/00; protocols for network security H04L63/00
• CPC Class Codes: H04L 12/40117 : Interconnection of audio or video/imaging devices home automation networks H04L12/2803; bitstream network arrangements specially adapted for distribution of digital video signals H04N7/24

Abstract

Secure computation environments are protected from bogus or rogue load modules, executables and other data elements through use of digital signatures, seals and certificates issued by a verifying authority. A verifying authority—which may be a trusted independent third party—tests the load modules or other executables to verify that their corresponding specifications are accurate and complete, and then digitally signs the load module or other executable based on tamper resistance work factor classification. Secure computation environments with different tamper resistance work factors use different verification digital signature authentication techniques (e.g., different signature algorithms and/or signature verification keys)—allowing one tamper resistance work factor environment to protect itself against load modules from another, different tamper resistance work factor environment. Several dissimilar digital signature algorithms may be used to reduce vulnerability from algorithm compromise, and subsets of multiple digital signatures may be used to reduce the scope of any specific compromise.

Claims

1. A method comprising:

digitally signing at least a first part of a first load module using a first key to yield a first digital signature;

digitally signing at least a second part of the first load module to yield a second digital signature; and

distributing at least the first digital signature and the second digital signature to a first remote electronic appliance, wherein the first remote electronic appliance comprises a protected processing environment operable to authenticate at least one of the first digital signature and/or the second digital signature before the first remote electronic appliance executes the first load module, the protected processing environment being resistant to tampering by a user of the first remote electronic appliance.

2. The method of claim 1, further comprising:

encrypting the first load module.

3. The method of claim 1, further comprising:

digitally signing at least a first part of a second load module using the first key to yield a third digital signature.

4. The method of claim 3, further comprising:

distributing at least the third digital signature to the first remote electronic appliance, wherein the protected processing environment is operable to authenticate at least the third digital signature before the first remote electronic appliance executes the second load module.

5. The method of claim 1, further comprising:

distributing at least the first digital signature and the second digital signature to a second remote electronic appliance, wherein the second remote electronic appliance comprises a protected processing environment operable to authenticate at least one of the first digital signature and/or the second digital signature before the second remote electronic appliance executes the first load module, wherein the protected processing environment is resistant to tampering by a user of the second remote electronic appliance.

6. The method of claim 5, in which the first remote electronic appliance and the second remote electronic appliance comprise a first public key for authenticating at least one of the first digital signature and/or the second digital signature.

7. The method of claim 1, in which the first load module, when executed by the first remote electronic appliance, is configured to cause the first remote electronic appliance to perform at least one action selected from the group consisting of:

record an aspect of usage of a piece of electronic content, prevent a user from making a copy of a piece of electronic content, charge a user a fee for viewing a piece of electronic content, enable the first remote electronic appliance to perform a financial transaction, and enable the first remote electronic appliance to play a piece of electronic content.

8. The method of claim 1, in which the first part of the first load module and the second part of the first load module comprise the same part of the first load module.

9. The method of claim 1, in which a second key that is different from the first key is used to sign the second part of the first load module.

10. The method of claim 1, further comprising:

securely distributing a first public key to the first remote electronic appliance, the first public key being configured for use in authenticating at least one of the first digital signature and/or the second digital signature.

11. A computer-readable medium comprising program code, the program code being operable, when executed by a computer system, to cause the computer system to perform steps comprising:

digitally signing at least a first part of a first load module using a first key to yield a first digital signature;

digitally signing at least a second part of the first load module to yield a second digital signature; and

distributing at least the first digital signature and the second digital signature to a first remote electronic appliance, wherein the first remote electronic appliance comprises a protected processing environment operable to authenticate at least one of the first digital signature and/or the second digital signature before the first remote electronic appliance executes the first load module, the protected processing environment being resistant to tampering by a user of the first remote electronic appliance.

12. The computer-readable medium of claim 11, further including program code that is operable, when executed by the computer system, to cause the computer system to perform the step of:

encrypting the first load module.

13. The computer-readable medium of claim 11, further including program code that is operable, when executed by the computer system, to cause the computer system to perform steps comprising:

digitally signing at least a first part of a second load module using the first key to yield a third digital signature; and

distributing at least the third digital signature to the first remote electronic appliance, wherein the protected processing environment is operable to authenticate at least the third digital signature before the first remote electronic appliance executes the second load module.

14. The computer-readable medium of claim 11, further including program code that is operable, when executed by the computer system, to cause the computer system to perform the step of:

securely distributing a first public key to the first remote electronic appliance, the first public key being configured for use in authenticating at least one of the first digital signature and/or the second digital signature.

15. The computer-readable medium of claim 11, in which a second key that is different from the first key is used to sign the second part of the first load module.

16. A system comprising:

means for digitally signing at least a first part of a first load module using a first key to yield a first digital signature;

means for digitally signing at least a second part of the first load module to yield a second digital signature; and

means for distributing at least the first digital signature and the second digital signature to a first remote electronic appliance, wherein the first remote electronic appliance comprises a protected processing environment operable to authenticate at least one of the first digital signature and/or the second digital signature before the first remote electronic appliance executes the first load module, the protected processing environment being resistant to tampering by a user of the first remote electronic appliance.

17. The system of claim 16, further comprising:

means for encrypting the first load module.

18. The system of claim 16, further comprising:

means for digitally signing at least a first part of a second load module using the first key to yield a third digital signature.

19. The system of claim 18, further comprising:

means for distributing at least the third digital signature to the first remote electronic appliance, wherein the protected processing environment is operable to authenticate at least the third digital signature before the first remote electronic appliance executes the second load module.

20. The system of claim 16, further comprising:

means for distributing at least the first digital signature and the second digital signature to a second remote electronic appliance, wherein the second remote electronic appliance comprises a protected processing environment operable to authenticate at least one of the first digital signature and/or the second digital signature before the second remote electronic appliance executes the first load module, wherein the protected processing environment of the second remote electronic appliance is resistant to tampering by a user of the second remote electronic appliance.

21. The system of claim 16, in which the means for digitally signing at least a second part of the first load module uses a second key that is different from the first key.

22. The system of claim 16, further comprising:

means for securely distributing a first public key to the first remote electronic appliance, the first public key being configured for use in authenticating at least one of the first digital signature and/or the second digital signature.